Tas makes the code structure clear, turning async code to sync, reducing the levels, avoiding callback hell / pyramid, is better than Promise, and can be used in Node.js and in browsers.

The tasks written by Tas do not need to use Promise / resolve / reject, generator / yield, async / await, so Tas is easier to use than Promise. And, also Tas is faster than Promise and promise libraries (Why).

Tas is a lightweight JavaScript logic framework (only 3KB gzipped), with no dependency. Tas is the abbreviation of "tasks".

1. Zero learning costs. Using the basic syntax of JavaScript, you can write the vast majority of tasks.
2. There is no need to write the tasks in the form of a callback, just in logical order.
3. Pass the data via return or this to the next function or tasks naturally.

In Node.js:

$ npm install tas --save

In Web / RequireJS:

Download Tas.js or Tas.min.js.

With Tas, we can turn complex logic or high-coupling logic into a set of mini-tasks. All mini-tasks are executed one by one.

tas("My first tasks", {
    t1: function () {
        return [1, 2, 3];
    },
    t2: function(a, b, c){
        console.log(a, b, c); // 1 2 3
        return [4, 5, 6];
    }
});

tas("My Second tasks", {
    t3: {
        t4: function (a, b, c) {
            console.log(a, b, c); // 4 5 6
            return [7, 8, 9];
        }
    },
    t5: {
        t6: function (a, b, c) {
            console.log(a, b, c); // 7 8 9
        }
    }
});

With Tas, we can write async code like writing sync code, easily avoiding callback hell / pyramid. All async tasks and sync tasks will be executed in the order we have written.

var a = 0;

tas.await(function(){
    a ++; // 1
  
    setTimeout(function(){      
        a ++; // 2
        tas.next();
    }, 1000);
});

// This task is executed after the previous async task execution is completed.
// This proves that all tasks are executed in the order we have written.
tas(function(){
    a ++ ; // 3
    console.log(a); // 3
})

We can use Tas as if using Promise. The tasks written by Tas do not need to use Promise / resolve / reject, generator / yield, async / await, so Tas is easier to use than Promise and promise libraries.

tas.promise(function(){
    // Use this.done to pass the data 
    ajax.get('https://api.github.com', this.done);
});

tas(function (err, data) {
    if (err) {
        console.log(err);
    }
    else {
        console.log(data);
    }
});

With Tas, when all dependencies (even including async module) execution are completed, the current module will get theire results. Everything becomes sync execution, no callback hell / pyramid.

a.js (dependency)

var tas = require('tas');
var a = 0;

tas.await(function(){
    a ++; // 1
      
    setTimeout(function(){
        a ++; // 2
        tas.next();
    }, 1000);
});

tas(function(){
    a ++; // 3
});

module.exports = {
    get: function(){
        return a; // 3
    }
};

b.js (dependency)

var tas = require('tas');
var a = 2;

tas.await(function(){
    a ++; // 3

    setTimeout(function(){
        a ++; // 4
        tas.next();
    }, 500);
});

tas(function(){
    a ++; // 5
})

module.exports = {
    get: function(){
        return a; // 5
    }
};

calc.js (depends on a.js and b.js)

var tas = require('tas');

// The tasks in a.js and b.js are executed in the order we have written.
var ma = require('./a');
var mb = require('./b');

// This task will be executed after all tasks are completed.
tas(function(){
    var a = ma.get(); // 3
    var b = mb.get(); // 5
    console.log(a + b); // 8
});

Clone the Tas repo first:

$ cd /path/to
$ git clone https://github.com/tasjs/tas.git

Run the test of examples in Node.js:

$ cd /path/to/tas/examples
$ node nodejs/__tas/test.js

Or view the source code of the examples online:

Run the test of examples in your browser:

$ cd /path/to/tas/examples
$ open web/__tas/test.html

Or view the source code of the examples online:

Run the test of examples in your browser:

$ cd /path/to/tas/examples
$ open web_requirejs/__tas/test.html

Or view the source code of the examples online:

Tas provides a small amount of APIs to control the flow, and they are simple and easy to use, so you can focus on the code itself without wasting time on mastering Tas.

Pass The Data

Async Tasks

As Promise

Break The Flow

Pass The Data

Async Tasks

As Promise

Break The Flow

Pass The Data

Async Tasks

As Promise

Break The Flow

Clone the Tas repo (if you have not done so yet):

$ cd /path/to
$ git clone https://github.com/tasjs/tas.git

$ cd /path/to/tas
$ npm test

Test with Node.js

$ cd /path/to/tas/test
$ node nodejs/test.js

Test in your browser:

$ cd /path/to/tas/test
$ open web/test.html

Test in your browser:

$ cd /path/to/tas/test
$ open web_requirejs/test.html

Tas does not use setTimeout or similar methods recommended by the Promise standard. With no delay, Tas is faster than Promise and promise libraries such as bluebird, Q, aigle, when.js, etc.

References:

[1] "This can be implemented with either a 'macro-task' mechanism such as setTimeout or setImmediate, or with a 'micro-task' mechanism such as MutationObserver or process.nextTick." See details

[2] "Modern browsers impose a minimum delay of 4ms on every setTimeout, regardless of how long you specify. " See details

[3] "setImmediate() is designed to execute a script once the current poll phase completes." See details

[4] "All callbacks scheduled via process.nextTick() are run at the end of a phase of the event loop (e.g. timers) before transitioning to the next phase. " See details

MIT

Copyright (c) 2017, Owen Luke